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arXiv · 2305.10976

Long-distance continuous-variable quantum key distribution with feasible physical noiseless linear amplifiers

Michele N. Notarnicola·Stefano Olivares
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Abstract

Noiseless linear amplifiers (NLAs) provide a powerful tool to achieve long-distance continuous-variable quantum key distribution (CV-QKD) in the presence of realistic setups with non unit reconciliation efficiency. We address a NLA-assisted CV-QKD protocol implemented via realistic physical NLAs, namely, quantum scissors (QS) and single-photon catalysis (SPC), and compare their performance with respect to the ideal NLA $g^{\hat{n}}$. We investigate also the robustness of two schemes against inefficient conditional detection, and discuss the two alternative scenarios in which the gain associated with the NLA is either fixed or optimized.

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Michele N. Notarnicola, Stefano Olivares. 2023-05-18. Long-distance continuous-variable quantum key distribution with feasible physical noiseless linear amplifiers. https://doi.org/10.1103/physreva.108.022404

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